Authorization: How do you assign a member to a role on the database level?

 Hi,
 I am using MS SQL Server database that I had created with the tool aspnet_regsql.exe to handle forms authorization. I set up two roles groups, one for administrators and the other for members then, I created two users using the ASP.NET configuration built in VS. One of my users is admin and the other is a member. This works fine, but when I create a new test member through my website not the configuration tool, this member is able to log in to the admin area as well as the members area. How do you assign a member to a role on the database level? Having a look at the DB, it looks like its done on the aspnet_UsersInRoles table. But even when I enter memberid and roleid on this table, it still doesn't work.
 Any suggestions will be very much appreciated.
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